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arXiv · 2307.09493

Erecting time telescope for photonic quantum networks

Shivang Srivastava·Dmitri B. Horoshko·Mikhail I. Kolobov
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Abstract

A time lens allows one to stretch or compress optical waveforms in time, similar to the conventional lens in space. However, a single-time-lens imaging system always imparts a residual temporal chirp on the image, which may be detrimental for quantum networks, where the temporal image interacts with other fields. We show that a two-time-lens imaging system satisfying the telescopic condition, a time telescope, is necessary and sufficient for creating a chirpless image. We develop a general theory of a time telescope, find the conditions for loss minimization, and show how an erecting time telescope creating a real image of a temporal object can be constructed. We consider several applications of such a telescope to making indistinguishable the photons generated by spontaneous parametric downconversion or single emitters such as quantum dots.

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Shivang Srivastava, Dmitri B. Horoshko, Mikhail I. Kolobov. 2023-07-18. Erecting time telescope for photonic quantum networks. https://doi.org/10.1364/oe.501609

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